Hello everyone, I recently installed an exchange server 2016 I followed the link from the post-installation tasks on technet microsoft.

This morning I am dedicated to the mailbox creation of tests to check the sending and receiving, etc .. And I noticed that when I create a mailbox, and in the creation screen i'm going to put the check on existing user and make pastry, I do not see nothing.

Whereas if the controller I create a domain user and put it under "Microsoft Exchange Security Groups" and I go to click again on pastry in the creation of the tape, the screen displays the user that I've just created. As if the "browse" was referring only to mydomain.local \ Microsoft Exchange Security Groups and also to mydomain.local \ Users. I could easily given that it is only a user, or move it to the right OU or recreate it with the same credentials. But if I had already created 100 users can not put me to recreate them or move them all. How do I resolve this? Thank you all!!